Kanga's child (3)
I believe the answer is:
roo
'kanga's child' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for roo that I've seen before include "Kanga's child (Pooh)" , "Kanga's baby (Pooh)" , "Small inhabitant of Hundred Acre Wood" , "Marsupial (dim.)" , "companion of Pooh" .)